A particle covers half of its total distance with speed v1 and the rest half distance with speed v2. Its average speed during the complete journey is
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(a) (v1v2)/(v1+v2) (b) (2v1v2)/(v1+v2) (c) […]
A man goes 10 m towards north, then 20m towards east, the displacement is
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(a) 22.5 m (b) 25 m (c) 25.5 m (d) 30 m
Correct Answer:
22.5 m
Explanation:
No […]
The ratio of the numerical value of the average velocity and average speed of a body is always
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(a) Unity (b) Unity or less (c) Unity or more (d) Less than unity
The rest mass of a body is m1. It moves with a velocity of 0.6c, then its relativistic mass if m then
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(a) m = m1 (b) m < m1 (c) m […]
Two balls are dropped from heights h and 2h respectively. The ratio of times of these balls to reach the earth is
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(a) 1 : √2 (b) √2 : 1 (c) 2 […]
A bullet comes out of the barrel of gun of length 2m with a speed of 800 m/s. The average acceleration of the bullet is
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(a) 160 m/s² (b) 60 km/s² (c) […]
An object of mass 3kg is at rest. Now a force F=6t² i⃗+4t j⃗ is applied on the object. Then velocity of object at t=3s is
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(a) 18 i⃗ + 3 j⃗ […]
If a body travels half the distance with velocity v1 and the next half with velocity v2, its average velocity will be given by
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(a) v=√(v1 x v2) (b) v= (v1 + […]
A particle is dropped from a building. It takes 4 sec for the particle to reach the ground. Then height of the building is (g=10m/s²)
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(a) 20 m (b) 40 m (c) […]
A particle under the action of a constant force moves from rest upto 20 seconds. If distance covered in first 10 seconds is S₁ and that covered in next seconds is S₂, then
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